The instant invention relates to a novel indication for myrrh, a pharmaceutical preparation in vaginal dosage form, a method for preparing a pharmaceutical preparation against menopausal symptoms, and a method for treating the human or animal body with myrrh to relieve menopausal symptoms.
Myrrh Resin
Myrrh is the oleo-gum resin obtained from stems and branches of Commiphora molmol Engler and other related species of Commiphora other than Commiphora mukul. Commiphora mukul—although sharing the genus name—cannot be used for obtaining myrrh. Commiphora molmol Engler is sometimes also referred to as Commiphora myrrha or Commiphora myrrha (Nees) Engler. Suited related species of Commiphora molmol for obtaining myrrh are Commiphora abyssinica Engler and Commiphora schimperi Engler. Pharmacopoeia myrrh is generally obtained from Commiphora molmol Engler, but the other related species, in particular those referred to above, are also well suited.
For medical purposes, myrrh is used as powdered resin, capsules, myrrh tincture and other galenical preparations for topical use.
Myrrh can be separated into three components: volatile oil (ca. 2 to 10%), alcohol-soluble resin (ca. 25 to 40%) and water-soluble gum.
The main constituents of myrrh essential oil are furanosesquiterpenes of various structural types together with sesquiterpenes. Furanosesquiterpenes are the source of its characteristic balsamic odour; a mixture of furanoeudesma-1,3-diene and lindestrene has the typical aroma of myrrh.
Myrrh essential oil is generally obtained by hydrodistillation, steam distillation, and solvent extraction. Extraction by carbon dioxide in the supercritical state is the state-of-the-art process that offers many advantages in obtaining volatile extracts. The mild extraction conditions give assurance against chemical reactions not taking place during the process; i.e. no hydrolysis, oxidation, or isomerisation taking place. Other possible extraction agents include nitrogen, hexane, methane, and ethane.
Marongiu et al.: “Chemical Composition of the Essential Oil and Supercritical CO2 Extract of Commiphora myrrha (Nees) Engl. and of Acorus calamus L.”, J. Agric. Food Chem. 53 (2005), 7939-7943 discloses the composition of myrrh extract obtained by different methods. The authors demonstrated that hydrodistillation (HD), steam distillation (SD) and supercritical extraction with carbon dioxide (SFE) yield similar results as far as main components and quantities extracted are concerned.
Myrrh is known for its wound healing effect. Dolara, P. et al.: “Local Anaesthetic, Antibacterial and Antifungal Properties of Sesquiterpenes from Myrrh”, Planta Medica 66 (2000), 356-358 describe the anaesthetic, antibacterial and antifungal properties of certain sesquiterpenes of myrrh.
U.S. Pat. No. 4,719,111 A discloses the external use of myrrh gum for treating decubitus ulcers.
U.S. Pat. No. 4,592,912 A discloses the topical use for the relief of or for the prevention of muscular aches, pains, cramps and muscular spasms such as are found, for example, in overexerted muscles, misused muscles, headaches and back aches.
U.S. Pat. No. 5,350,774 A describes the topical treatment of skin disorders with myrrh.
U.S. Pat. No. 5,248,503 A discloses the utilization of myrrh as food or dietary supplement.
U.S. Pat. No. 6,077,513 A discloses a pharmaceutical composition containing myrrh oil and myrrh resin as the active ingredients therein for treating schistosomiasis.
Physiology of Menopausal Vaginal Symptoms
The menopause is defined as the permanent cessation of cyclical menstruation due to loss of ovarian follicular activity. The decline in estrogen concentration is associated with both acute and long-term effects. Established acute symptoms are vasomotor instability, manifesting as hot flushes and night sweats, and vaginal atrophy, manifesting as vaginal dryness, itching, burning, and discomfort.
Menopausal symptoms may be managed by using hormone replacement therapy (HRT) with estrogens, with or without progestogens. Adverse effects of HRT include an increased risk of breast cancer, ovarian and endometrial cancer, an increased risk of venous thromboembolism, stroke, dementia, gallstone formation and cholecystectomy. It is now generally recommended that menopausal HRT used to relieve vasomotor and vaginal symptoms should be given at the lowest effective dose for no longer than necessary. But to withdraw HRT means recurrence of menopausal symptoms.
Density of estrogen receptors is highest in endometrium and vagina. A drop in estrogen levels results in                a decrease in mitotic activity, so the vaginal lining becomes thinner and more fragile;        a drop in collagen content in the connective tissue;        decreased blood flow and decreased vaginal lubrication;leading to vaginal symptoms and findings of pallor, dryness and decreased rugosity of the vaginal mucosa.        
US 2003/0170325 A1 discloses compositions in gel or suppository form for the treatment of vaginal dryness. The compositions comprise herbal compounds with or without vitamin. However, this patent application does not suggest using extracts of myrrh for the treatment of vaginal dryness.